SC-04-03 meeting report, New York, 2011-10

Report of the meeting of the SC-04-03 Working Group on loudspeaker modeling and measurement of the SC-04 Subcommittee on Acoustics, held in conjunction with the AES 131st Convention in New York, NY., 2011-10-22

The meeting was convened by chair S. Hutt.

The agenda and the report of the previous meeting were accepted as written.

Open projects

AES2-R Review of AES2-1984 (r2003): AES Recommended Practice - Specification of loudspeaker components used in professional audio and sound reinforcement
The current AES2-R draft, together with a number of comments received on the group's e-mail reflector, were discussed in the meeting to produce a number of revisions.

Urgency: Release of AES2-R part 1 is critically behind schedule and must be approved for release promptly in order to replace the current obsolete document, which should have been withdrawn some time ago. If the committee cannot come to consensus to release the document, the old document must still be withdrawn due to it containing erroneous information.

Clause 5.3: On 2011-02-11, C. Hughes uploaded an edited draft of section 5.3 to include insertion of section 5.3.1 and 5.3.2. In general, reflector comments were favorable. The secretary will insert these proposed changes into the document. Hughes' draft Section 5.3 AES2-R_MaxContSPL-20110211 can be downloaded from the working group document site.

Annex B: The executable noise generating program needs to be completed promptly or reference to it will be deleted from the document. Unfortunately some programming challenges have delayed completion of the executable. R. Mihelich has volunteered to finish the executable, if possible. C. Struck volunteered to review the .m files before releasing. Users with native Matlab can run these .m files.

Secretary Yonge noted that Annex B is informative and therefore not necessary for the publication of the document.

Crest factor: D. Gunness volunteered to write up and post to the reflector some statements about systems crest factor and that it might be better to change crest factor to 12dB from 6dB so that it is better matched with the crest factor found in real-life systems. Comment is requested via the e-mail reflector.

Development projects

AES-X129 Loudspeaker Distortion Perception and Measurement
X129 has been a productive and interesting project with a body of work available for review and use. Thanks are due to all the members that have contributed and in particular to Dr. Alex Voishvillo. The scope of the project has been satisfied.

This project was proposed to be retired.

Liaisons

No liaison matters were raised.

New Projects

No new projects were proposed.

New Business

There was no new business.

The next meeting will be scheduled in conjunction with the AES 132nd Convention in Budapest, Hungary, 2012-04.